The malfunctioning of an aortic valve results in cardiac insufficiency and hence in a situation that is potentially fatal for the patient. For repair of such a defect, artificial aortic valves have been developed which are implanted as a substitute for the damaged valve in complex and risky open-heart surgery (sternotomy). The operation becomes particularly difficult when there is strong calcareous degeneration on the natural valve because painstaking attention must be paid during removal in order to ensure that calcification particles will not enter the blood circulation and cause there thromboses at other sites in the body. It is common to fasten the replacement valves—which are either mere engineering products or derived from porcine or other tissue valves—by suturing in the place of the removed valve.
There are numerous approaches in the development of methods simplifying this complex procedure of aortic-valve replacement in terms of both the surgical technique and the discomfort and strain for the patient, aiming at a minimally invasive technique of replacement of the aortic valve. In these approaches, the operation is performed via the femoral artery or even through the groin.
In view of the very restricted possibilities of access in the aortic arch, it is inevitable to adopt complex surgical strategies, firstly for explantation of the calcified aortic valve and secondly for implantation of an artificial valve in situ. Apart from all difficulties involved in the surgical operation—even though minimally invasive surgery is concerned that operates on advanced catheter technology—a maximum of concentration and above all a steady hand is demanded from the surgeon, specifically as the individual steps of surgical handling are within the millimeter range and there below. With the minimally invasive operation being performed with a sustained natural function of the heart, it is moreover important to carry out the operation as quickly as possible in order to keep the strain on the cardiac system at a minimum, which means that an operation of this kind is performed under a certain pressure in terms of time.
A special aspect is the ablation of the calcified aortic valve that must be removed completely from the aorta as quickly as possible, without lesion of adjoining unaffected tissue regions, specifically as the ablation involves mostly the application of mechanically acute cutting tools. Furthermore, it is important to ensure that severed tissue fragments or calcification particles will be extracted from the blood stream without any residues so as to avoid the occurrence of embolism or thromboses.